1. Field of the Invention
The present invention relates to the technology applied to the technological field of a scanning laser microscope.
2. Description of the Related Art
Conventionally, a scanning laser microscope has been well known as an apparatus for irradiating a specimen (sample) with a light beam from a light source for two-dimensional scanning, detecting a light (a reflected light, a transmission light, fluorescence, etc.) from the specimen using a photodetector, converting the detected light into an electric signal by a photoelectric transducer, and obtaining image data.
Briefly described below is the configuration and the operation of the conventional scanning laser microscope.
A specimen is irradiated with a light beam from a light source for two-dimensional scanning, a light (a reflected light, a transmission light, fluorescence, etc.) depending on the material and the shape of the specimen is detected by a photodetector, and the detected light is converted into an electric signal by a photoelectric transducer. Then, a converted electric signal is converted into image data which is a digital signal by an A/D converter, and the obtained image data is stored in the image memory. An image based on the image data stored in the image memory is displayed on a display unit of a computer.
Thus, when a specimen is observed using a scanning laser microscope, an image of the specimen is obtained by obtaining image data depending on the specimen, and simultaneously, for example, it can be necessary to measure and store the reaction of a target under observation (specimen) such as a cell, etc. which changes with time in a given period by a change of the temperature or the stimulus given to the cell.
In this case, the CPU of a computer controlling the scanning laser microscope performs the process of controlling a scanning laser microscope such as light beam scanning, etc., manipulating image data, transferring and displaying an image of the image data, etc., records the data obtained from an external detector (various sensors, etc.), various input device, etc. in real time, performs a visualizing process by preparing a graph, etc. from the recorded data as necessary, and displays the result on the display device connected to the computer. The data obtained from the above mentioned external detector, various input device, etc. is an example of an external signal, and can be referred to as an event signal.
As described above, the CPU which enters a high load state by simultaneously performing various processes such as light beam scanning, fetching image data, etc. is sometimes incapable of immediately responding to an event signal. As a result, there can be undesired delay between the timing in inputting an event signal, that is, the timing in generating the event signal, and the timing in recording the event signal.
If an event signal (including an interruption signal, etc.) is input into the CPU in the high load state during the two-dimensional scanning in the conventional scanning laser microscope, then the CPU cannot immediately respond to the signal, and there occurs a delay between the time when the event signal occurs and the time when a response is returned.
Regarding the problem, for example, Japanese Patent Laid-open No. Hei 8-287860 discloses the technology of improving the response time from the start of an operation to due control by directly providing a SEM (scanning electronic microscope) control unit with a command relating to a more responsive process when a SEM control command is issued to the SEM control unit as an operation signal by input unit such as a keyboard, a mouse, etc.
As described above, if the CPU of a computer simultaneously performs various processes such as control of the scanning laser microscope by light beam scanning, etc., manipulation of image data, monitor of various sensors, storage and process of signals obtained from various sensors, etc., then a heavy load is applied to the CPU, for example, the CPU cannot immediately respond to signals (event signals) from various sensors, and there occurs a delay between the time when the signals from various sensors are generated and the time when the signals are stored.